α-decay half-lives: Empirical relations

Sets of simple relations for evaluation of the half-lives of α transitions between the ground states of parent and daughter nuclei are presented. Experimental data for half-lives in 344 α emitters are used for obtaining the sets of equations. The sets of simple expressions are found for the whole data set as well as for heavy and light subsets of nuclei. Terms related to the orbital moment and parity of α transition are introduced for the case of α decay in even-odd, odd-even, and odd-odd nuclei. The electron screening effect is taken into account.